Highly chemo- and stereoselective Fe-catalyzed alkenylation of organomanganese reagents
作者:Gérard Cahiez、Sophie Marquais
DOI:10.1016/0040-4039(96)00116-5
日期:1996.3
Organomanganese chlorides react with alkenyl iodides, bromides and chlorides in the presence of 3% Fe(acac)3. The reaction takes place under very mild conditions (THF-NMP, rt, 1h) to afford the substituted olefin in excellent yields with a high stereo- and chemoselectivity. Thus an unprotected keto alkenyl chloride selectively gives the corresponding keto olefin. From a preparative point of view, this
Ironing out the kinks: Efficientnew catalytic systems based on iron thiolates are described for the iron‐catalyzed cross‐coupling of alkyl Grignard reagents with alkenylhalides (see scheme). The reaction is highly chemo‐ and stereoselective. With this new procedure, the use of N‐methylpyrrolidone as a co‐solvent is no longer required.
A Novel Synthesis of Internal Alkenyldialkylborane by the Reaction of 1-Halo-1-alkenyldialkylborane with Grignard Reagent
作者:Akira Arase、Masayuki Hoshi、Yuzuru Masuda
DOI:10.1246/bcsj.57.209
日期:1984.1
To synthesize internal alkenyldialkylboranes, coupling reactions were carried out by using 1-halo-l-alkenyldialkylboranes and Grignardreagents. Hydrogen peroxide oxidation and protonolysis with acetic acid of the reaction product revealed that internal (E)-alkenyldialkylborane was formed in 60–90% yield.
Reaction of Trialkyl(dibromomethyl)silanes or 1,2-Bis(dibromomethyl)benzene with Triorganomanganates. A Facile and Selective Synthesis of Alkenylsilanes and 1,2-Diaryl-1,2-dihydrobenzocyclobutenes
stereoselectivity in good yields. The reaction of trialkyl(dibromomethyl)silanes with alkylmagnesium halides proceeded in the presence of a catalytic amount of manganese(II) chloride. Treatment of 1,2-bis(dibromomethyl)benzene with triphenylmanganate gave 1,2-diphenyl-1,2-dihydrobenzocyclobutene.
用衍生自氯化锰 (II) 和三摩尔量的格氏试剂或烷基锂的三烷基锰酸盐处理三烷基(二溴甲基)硅烷,以良好的收率提供具有高立体选择性的(E)-1-三烷基甲硅烷基-1-烯烃。三烷基(二溴甲基)硅烷与烷基卤化镁的反应在催化量的氯化锰(II)存在下进行。用三苯基锰酸盐处理 1,2-双(二溴甲基)苯得到 1,2-二苯基-1,2-二氢苯并环丁烯。
Tandem Application of C–C Bond-Forming Reactions with Reductive Ozonolysis
作者:Rachel Willand-Charnley、Patrick H. Dussault
DOI:10.1021/jo3015775
日期:2013.1.4
Several variants of reductiveozonolysis, defined here as the in situ generation of aldehydes or ketones during ozonolytic cleavage of alkenes, are demonstrated to work effectively in tandem with a number of C–C bond-forming reactions. For reactions involving basic nucleophiles (1,2-addition of Grignard reagents, Wittig or Horner–Emmons olefinations, and directed aldol reactions of lithium enolates)